It is sometimes useful to have an indication of the complexity of a data signal. For example, it has been proposed to multiplex a plurality of coded video signals, each encoded using a constant bit rate (CBR) encoder. The bit rate allocated to each of the CBR encoders is dynamically varied, based on both the coding complexity of the video signal being encoded, and the combined complexities of all of the video signals being multiplexed. In such a system, video signals having relatively high coding complexity are allocated a higher bit rate than those having relatively low coding complexity.
One known measure of the complexity of a data signal is the number of bits necessary to encode the signal using a variable bit rate (VBR) encoder: more bits indicate higher complexity, and conversely, fewer bits indicate lower complexity. A VBR encoder is a complex electronic system, however, and adding a VBR encoder for each signal to be multiplexed to determine the complexity of that signal is expensive and results in lowered reliability due to the added complex circuitry. It is desirable to provide an indication of the complexity of an input data signal, without the added expense and decreased reliability of a complex electronic system.